[#557]Fix error when there are no valid server strings

sslyze/__main__.py

@@ -12,6 +12,7 @@
     SslyzeOutputAsJson,
     ServerScanResultAsJson,
 )
+from sslyze.json.json_output import InvalidServerStringAsJson
 from sslyze.mozilla_tls_profile.mozilla_config_checker import (
     MozillaTlsConfigurationChecker,
     ServerNotCompliantWithMozillaTlsConfiguration,
@@ -56,13 +57,14 @@ def main() -> None:
             scan_commands_extra_arguments=parsed_command_line.scan_commands_extra_arguments,
         )
         all_server_scan_requests.append(scan_request)
-    assert all_server_scan_requests
 
-    sslyze_scanner.queue_scans(all_server_scan_requests)
+    # If there are servers that we were able to resolve, scan them
     all_server_scan_results = []
-    for result in sslyze_scanner.get_results():
-        # Results are actually displayed by the observer; here we just store them
-        all_server_scan_results.append(result)
+    if all_server_scan_requests:
+        sslyze_scanner.queue_scans(all_server_scan_requests)
+        for result in sslyze_scanner.get_results():
+            # Results are actually displayed by the observer; here we just store them
+            all_server_scan_results.append(result)
 
     # Write results to a JSON file if needed
     json_file_out: Optional[TextIO] = None
@@ -74,6 +76,9 @@ def main() -> None:
     if json_file_out:
         json_output = SslyzeOutputAsJson(
             server_scan_results=[ServerScanResultAsJson.from_orm(result) for result in all_server_scan_results],
+            invalid_server_strings=[
+                InvalidServerStringAsJson.from_orm(bad_server) for bad_server in parsed_command_line.invalid_servers
+            ],
             date_scans_started=date_scans_started,
             date_scans_completed=datetime.utcnow(),
         )
@@ -84,6 +89,10 @@ def main() -> None:
     if parsed_command_line.should_print_json_to_console:
         sys.exit(0)
 
+    if not all_server_scan_results:
+        # There are no results to present: all supplied server strings were invalid?
+        sys.exit(0)
+
     # Check the results against the Mozilla config if needed
     are_all_servers_compliant = True
     # TODO(AD): Expose format_title method

sslyze/json/json_output.py

@@ -1,6 +1,6 @@
 from datetime import datetime
 from pathlib import Path
-from typing import List, Optional
+from typing import List, Optional, TYPE_CHECKING
 from uuid import UUID
 
 import pydantic
@@ -41,6 +41,9 @@
 from sslyze.scanner.models import AllScanCommandsAttempts
 from sslyze.server_setting import ConnectionTypeEnum, ServerNetworkLocation
 
+if TYPE_CHECKING:
+    from sslyze.cli.server_string_parser import InvalidServerStringError
+
 
 class _BaseModelWithOrmModeAndForbid(pydantic.BaseModel):
     class Config:
@@ -211,12 +214,30 @@ def from_orm(cls, server_scan_result: ServerScanResult) -> "ServerScanResultAsJs
 ServerScanResultAsJson.__doc__ = ServerScanResult.__doc__  # type: ignore
 
 
+class InvalidServerStringAsJson(_BaseModelWithOrmModeAndForbid):
+    """A hostname:port string supplied via the command line that SSLyze was unable to parse or resolve.
+    """
+
+    server_string: str
+    error_message: str
+
+    @classmethod
+    def from_orm(cls, invalid_server_string_error: "InvalidServerStringError") -> "InvalidServerStringAsJson":
+        return cls(
+            server_string=invalid_server_string_error.server_string,
+            error_message=invalid_server_string_error.error_message,
+        )
+
+
 class SslyzeOutputAsJson(pydantic.BaseModel):
     """The "root" dictionary of the JSON output when using the --json command line option.
     """
 
+    invalid_server_strings: List[InvalidServerStringAsJson] = []  # TODO(AD): Remove default value starting with v6.x.x
     server_scan_results: List[ServerScanResultAsJson]
+
     date_scans_started: datetime
     date_scans_completed: datetime
+
     sslyze_version: str = __version__
     sslyze_url: str = __url__

tests/test_main.py

@@ -1,6 +1,9 @@
 import sys
 from unittest import mock
 
+import pytest
+
+from sslyze import SslyzeOutputAsJson
 from sslyze.__main__ import main
 
 
@@ -12,3 +15,30 @@ def test(self):
         # When running the CLI, it succeeds
         with mock.patch.object(sys, "argv", command_line):
             main()
+
+    def test_no_valid_server_strings(self):
+        # Given a command line to launch the sslyze CLI, but the supplied server string is invalid
+        command_line = ["sslyze", "--quiet", "--compression", "invalid.server.testests"]
+
+        # When running the CLI, it succeeds
+        with mock.patch.object(sys, "argv", command_line):
+            # And the CLI exited early because there is no actual server to scan
+            with pytest.raises(SystemExit):
+                main()
+
+    def test_json_out_in_console(self, capsys):
+        # Given a command line to launch the sslyze CLI and return results as JSON in the console
+        command_line = ["sslyze", "--json_out=-", "--compression", "www.google.com"]
+
+        # When running the CLI, it succeeds
+        with mock.patch.object(sys, "argv", command_line):
+            with pytest.raises(SystemExit):
+                main()
+
+        # And the JSON output was printed to the console
+        json_output = capsys.readouterr().out
+        assert json_output
+
+        # And the JSON output has the expected format
+        parsed_output = SslyzeOutputAsJson.parse_raw(json_output)
+        assert parsed_output